1. Technical Field of the Invention
The present invention relates to an electro-optical device and a method of manufacturing the same, and an electronic apparatus. More specifically, the present invention relates to an electro-optical device which is suitably used as a transflective electro-optical device in an electronic apparatus such as a cellular phone, a portable personal computer, or the like, and which is capable of improving the color density and color purity of a transmissive image display without deteriorating the brightness of a reflective image display, a method of manufacturing the electro-optical device, and an electronic apparatus.
2. Description of the Related Art
In recent years, electro-optical devices have been widely used as display sections of electronic apparatus such as a cellular phone, a portable personal computer, etc. The electro-optical devices have taken various forms according to the desired purposes. For example, when the device is used in a dark place or the luminance of an image display section is particularly required, a transmissive electro-optical device which uses, for displaying, light incident from a light source at the back of the electro-optical device is used, while when the device is used in a sufficiently bright place or the luminance of an image display section is not particularly required, a reflective device which uses, for displaying, external light such as natural light or room light incident from the front of the device to be reflected is used.
Furthermore, a so-called transflective electro-optical device capable of both transmissive display and reflective display can also be used. The transflective electro-optical device comprises a colored layer to permit a full-color display, and is capable of suppressing power consumption by turning on and off a light source according to operation conditions, and thus the transflective electro-optical device is useful as a full-color electro-optical device of a portable electronic apparatus using a charging battery or the like as an electric power supply.
However, such a transflective electro-optical device uses two different display systems and thus has the following problem.
When the transflective electro-optical device is used as a reflective type, external light incident from the front of the image display section passes through a colored layer, and is then reflected by a transflective film, and again passes through the colored layer. Therefore, the distance of passage through the colored layer is two times or more that with transmissive type in which light passes through the colored layer only one time, thereby decreasing the brightness of a display image. In order to achieve a sufficiently bright image display when the device is used as the reflective type, it is necessary to decrease the thickness of the colored layer or the pigment concentration. However, in use as the transmissive type under this condition, an image display with a sufficient color tone (color density) and color purity cannot be obtained. Conversely, when the condition of the colored layer is set by increasing the thickness of the colored layer or the pigment concentration to obtain a transmissive image display with a sufficient color density, a reflective image display with sufficient brightness cannot be obtained. Therefore, the achievement of a reflective image display with sufficient color brightness and the achievement of a transmissive display with a sufficient color density (color concentration) and color purity is difficult to obtain.
The “color purity” can be defined by the content of a specified wavelength in the wavelengths of light transmitted through the colored layer. For example, the color purity can be represented by the half-width of a peak wavelength in a transmittance curve drawn in a graph showing transmittance on the Y axis, and wavelength on the X axis. Namely, the color purity increases as the half-width decreases.
An object of the present invention is to provide an electro-optical device which is suitably used as a transflective electro-optical device in an electronic apparatus such as a cellular phone, a portable personal computer, or the like, and which is capable of improving the color density and color purity of a transmissive image display without deteriorating the brightness of a reflective image display, and a method of manufacturing the electro-optical device, and an electronic apparatus.